Hospitals routinely monitor physiological parameters of patients from first entry until final release. Originally, this was performed by one or more patient monitoring devices, such as a heart rate monitor, an EKG monitor, an SpO2 monitor, and so forth. These physiological parameters were separately detected by separate pieces of equipment, possibly manufactured by respectively different manufacturers. The monitoring equipment included the connections to the patient necessary to measure the physiological parameter and a display device of the type necessary to display the physiological parameter in an appropriate manner. A healthcare worker, such as a nurse, visited the patient's location and looked at each separate system to accumulate the patient's vital signs.
Current systems have integrated measurement of some of the physiological parameters (e.g. EKG, SpO2, etc.) into a single patient monitoring device. Such a device includes the patient connections necessary to measure the physiological parameters measurable by the device and a display device which can display the measured physiological parameters in an appropriate manner. Such patient monitors may be considered to be partitioned into two sections. A first, operational, section controls the reception of signals from the electrodes connected to the patient and performs the signal processing necessary to calculate the desired physiological parameters. A second, control, status and communication, section interacts with a user to receive control information and with the operational section to receive the physiological parameters, and displays status information and the values of the physiological parameters in an appropriate manner. Either or both of these sections may include a computer or processor to control the operation of that section. This approach has an economic advantage since the control, status and communication section is shared among the parameter monitoring functions.
Such patient monitors may also be connected to a central hospital computer system via a hospital network. In this manner, data representing patient physiological parameters may be transferred to the central hospital computer system for temporary or permanent storage in a storage device. Data received from the patient monitors may also be monitored by a person, such as a nurse, at the central location. The stored data may be retrieved and analyzed by other healthcare workers via the hospital network. Patient monitors in such a networked system include a terminal which is capable of being connected to and communicating with the hospital network. In such a patient monitor, the control, status and communication section controls the display of the physiological parameters, and also the connection to the hospital network and the exchange of the physiological parameters with other systems, such as other patient monitors and/or the central computer storage device, via the hospital network.
Such patient monitoring modules may also be portable. That is, they may operate while being transported with a patient who is being moved from one location to another in the hospital, for example, between a patient room and a therapy or operating room. A portable patient monitor consists of a base unit, and a portable unit which may be docked and undocked from the base unit. Base units may be placed at appropriate locations in the hospital. They are permanently connected to the hospital network and receive power from the power mains. The portable unit includes the necessary patient connections, connections for docking with base units, and a display screen. The portable unit also includes a processor which controls the operation of the portable unit The portable unit further includes a battery and an internal memory device.
While the portable unit of the patient monitor is docked, the batteries are recharged, and data representing physiological parameters are transmitted to the central hospital computer through the base unit via the hospital network. While the portable unit of the patient monitor is undocked, it runs on battery power. During transportation, the patient monitor continues to receive and display physiological parameters, and stores a record of those parameters in the internal memory device. If a base unit is available at the destination, the portable unit may be docked there. Communications is reestablished with the hospital central computer, and battery recharging commenced. At this time, data representing the previously stored parameters is retrieved from the internal memory device and transmitted to the storage device in the central hospital computer via the hospital network.
In such a patient monitor, the control, status and communication section controls display of the physiological parameters and communication of those parameters to the hospital network via the docking unit, and also detection of docking and undocking, control of power (either from the base unit when docked or the internal battery when undocked), storage of physiological parameter data in internal memory when the patient monitor is undocked, and transmission of stored physiological parameter data when the patient monitor is redocked.
Patient monitors have also been adapted to be used to transmit information to the hospital network from other modules. These modules may be patient monitoring modules measuring physiological parameters which are not measured by the patient monitor, or patient treatment modules reporting the status of treatments being provided to the patient. Such patient monitors include input terminals, or wireless input ports, to which these other monitoring modules are connected. Information from these modules is passed through the patient monitor to the hospital network through the base unit.
FIG. 1 is a block diagram of a hospital 100 operating in the manner described above. In FIG. 1, four rooms in a hospital are illustrated: an operating room 102, an intensive care unit (ICU) room 104, an emergency room 106 and another critical care room 108. The operating room 102, the ICU room 104 and the emergency room 106 include a patient monitor device as described above. Each patient monitor includes a connection to a critical care area network 110, either directly from the patient monitor or through a base unit (not shown). Each patient monitor also includes patient connections to electrodes attachable to the patient, not shown to simplify the figure. The patient monitors also receive data from other devices and forward that data to the critical care area network. In the operating room 102, an anesthesia device and fluid management device are coupled to the critical care area network 110 through the patient monitor; in the ICU room a ventilator device and fluid management device are coupled to the critical care area network 110 through the patient monitor; and in the emergency room 106 a ventilator device is coupled to the critical care area network 110 through the patient monitor. In the other critical care room 108 a ventilator device is coupled directly to the critical care area network 110, either directly or through its own base unit.
The modules illustrated in FIG. 1 operate independently of each other, and each includes its own computer or processor controlling the module. This requires the presence of a base unit for each separate module. In an operating room, where many such modules may be in use concurrently, this requires space, and power. Further, each device may be docked in a base unit for that type of device. That is, a patient monitor device may be docked in a patient monitor base unit, a fluid monitoring device may be docked in a fluid monitoring device base unit, and so forth.
A patient monitor is passive in the sense that it monitors physiological parameters of the patient to which it is attached. However, other medical devices are active in the sense that their operation affects the patient in some manner. For example, the anesthesia device controls the administration of anesthesia to a patient, e.g. during an operation; the fluid management device controls the administration of fluids (blood, saline, and/or medication) to a patient; the ventilator device assists or controls breathing of a patient, e.g. during an operation, and so forth. The active devices also include a computer or processor which controls the operation of the device. These devices also may be connected to a hospital network through a base unit. This allows a central location to monitor and to control the active device. As with the patient monitoring device, an active device, such as a fluid monitoring device, may be portable in the sense that a control module, including a processor, may be undocked from a fixed unit. This control module continues to operate the device, at the last received control settings, e.g. while a patient is transported from one location to another. When at the new location, the control module may be docked in a fixed unit at the new location and control by a central computer resumed.
The existing processing and display systems, described above. used in patient monitoring and treatment have numerous limitations. Such existing processing systems employ different software for monitor computers, anesthesia computers, ventilation computers, and fluid management computers. Further, system devices are typically transported and connected to a particular corresponding type of medical device computer (e.g., a monitor device may be transported and connected to a corresponding monitor computer). Further, in existing systems, medical device processing devices and displays are typically able to view and control parameters and functions of other like devices, that is, a monitor processing device and display is limited to be able to view and control parameters and functions of another monitor processing device and display. In addition, existing systems typically derive patient parameters using specialized equipment and devices individually tailored to process a specific corresponding type of patient parameter. These devices require multiple individual electrical connections and fail to provide inter-device communication and central parameter processing capability.
Consequently to provide a desired therapy to a patient, the patient monitoring and/or treatment modules required to provide that therapy is assembled at the patient bedside. They are attached to the patient, and separately configured. Further, to provide the desired therapy may require changing the settings of one of the patient treatment devices based on readings derived from another device, are required. Because the different patient monitoring and/or treatment modules are from different sources and include different user interfaces, there is a significant risk of a mistake being made in the settings of one device based on the readings from another. In order to minimize such mistakes, detailed instructions are provided to the clinician for operating the patient monitoring and/or treatment devices required to provide the desired therapy, and the requirement for human interaction with the patient monitoring and/or treatment modules slows the process of providing the desired therapy.
A wide variety of lung recruitment maneuvers are desirable respiratory therapies in the event of acute restrictive lung failure. It can be therapeutically beneficial, especially at an early stage, to reventilate lung areas which have collapsed in the course of the illness by inflating them with an applied pressure or volume over an adequate period of time. Following such a maneuver, the lungs need to be stabilized with an adequate positive end expiratory airway pressure (PEEP). The PEEP required for this is identified by measures such as an expiratory low flow maneuver or a slow step-by-step reduction in PEEP until the first manifestation of a so-called derecruitment—that is, a disproportionately high decrease in volume relative to the reduced pressure.
Therapeutic limitations, both in recruitment maneuvers and in maneuvers to determine the ideal ventilation settings, are typically the high pressures exerted over a long period of time on the chest cavity which reduce the venous return flow to the right heart and thus the cardiac output and the arterial pressure. As a countermeasure, a patient may be provided with an additional volume of circulating blood, in an effort to maintain an appropriate cardiac output and provide an adequate degree of blood flow (i.e., perfusion) to important tissues. However, the additional volume of circulating blood may result in the negative effect of increasing the intrathoracal pressure in the patient's chest cavity. Furthermore, if the pressure is suddenly and drastically reduced, the blood volume suddenly flowing back out of the capacity vessels (i.e., veins) into the right heart may overstrain the heart, particularly in patients with a coronary heart condition. If there is an insufficiency of the left heart, excessive volume input can lead to lung edema. A system according to invention principles addresses these deficiencies and related problems.